actually, buying early stages plane will make you play training with lots of enemy planes with tailgunners, which is hard for beginners. From my view F4F-4 Wildcat and stuffs are the best choice starters can get. Most of all, there is no enemy planes with tailgunners in the training. Plus, they give 10points for each kills, while early stages only gives you 8 or 9. (you can get 11 or 12 for later stages planes, but that costs something like 3000 aps, which is too expensive).